Engine quites after 30 seconds of idle
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Bill
I am not sure if you are able to help me on this issue but I am at a total loss for a solution.
I have a Mintor 23 CC Glow engine which shares many of the internal parts from the OS 140 RX engine. The pump is an OS pump and the carb design is very close to the 140 RX design.
The engine starts first flip and runs great at throttle but will die after about 30 seconds of idle. Per the OS manual, this in indicates the low end is lean however I have the low end cam adjusted to the max. I have also run it to the lean side and it still dies. I would like your opinion on some of my thoughts for the root cause.
A few comment on the engine condition
-The piston ring is relatively new
-Bearings are new stainless type
-I am using a mac header with a BCP pipe. Header is quite long so I get an even throttle response.
1) Will a worn pump cause this issue?. I have never adjusted it as warned in the OS manual.
2) Do you service these pumps?
2) The tank center line is located about 6 inches below the center line of the carb. Can this be too much head for the pump at idle?
3) I have inspected the o rings in the carb and they do look flattened however there seems to be a good seal. I have ordered new o rings and will replace them. Can this possible cause the issue?
You help is greatly appreciated.
Dave
I am not sure if you are able to help me on this issue but I am at a total loss for a solution.
I have a Mintor 23 CC Glow engine which shares many of the internal parts from the OS 140 RX engine. The pump is an OS pump and the carb design is very close to the 140 RX design.
The engine starts first flip and runs great at throttle but will die after about 30 seconds of idle. Per the OS manual, this in indicates the low end is lean however I have the low end cam adjusted to the max. I have also run it to the lean side and it still dies. I would like your opinion on some of my thoughts for the root cause.
A few comment on the engine condition
-The piston ring is relatively new
-Bearings are new stainless type
-I am using a mac header with a BCP pipe. Header is quite long so I get an even throttle response.
1) Will a worn pump cause this issue?. I have never adjusted it as warned in the OS manual.
2) Do you service these pumps?
2) The tank center line is located about 6 inches below the center line of the carb. Can this be too much head for the pump at idle?
3) I have inspected the o rings in the carb and they do look flattened however there seems to be a good seal. I have ordered new o rings and will replace them. Can this possible cause the issue?
You help is greatly appreciated.
Dave
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If it's not an O.S., we cannot comment on it. We have no familiarity with that brand of engines.
O.S. pumps are not serviceable.
If an engine quits after idling a bit, it can be too rich or too lean. If it graduallly slows and then quits, it rich. If it runs a bit, speeds up a little and quits, it's too lean.
Poor idle can also be caused by a bad piston/ring/liner fit, a bad glow plug, or problem in the fuel system (air leaks, blockages, etc.).
O.S. pumps are not serviceable.
If an engine quits after idling a bit, it can be too rich or too lean. If it graduallly slows and then quits, it rich. If it runs a bit, speeds up a little and quits, it's too lean.
Poor idle can also be caused by a bad piston/ring/liner fit, a bad glow plug, or problem in the fuel system (air leaks, blockages, etc.).
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Bill
I wanted to give you a follow up on this issue.
I disassembled the carb and noticed the O rings where a little flattened. I removed them and they sat on the bench for a day. When I went to try and put them back they snapped in half with a slight bend. Since finding original parts for this engine is almost impossible, I replaced the entire Carb with a new OS140RX carb. Idled perfect and ran fine on the factory setting. Maybe tad rich, but had a number of flights today and it ran great.
Now you can say that the pump will work just fine with the tank 5" below center line
Dave
I wanted to give you a follow up on this issue.
I disassembled the carb and noticed the O rings where a little flattened. I removed them and they sat on the bench for a day. When I went to try and put them back they snapped in half with a slight bend. Since finding original parts for this engine is almost impossible, I replaced the entire Carb with a new OS140RX carb. Idled perfect and ran fine on the factory setting. Maybe tad rich, but had a number of flights today and it ran great.
Now you can say that the pump will work just fine with the tank 5" below center line
Dave